WorksheetsCHAPTER 11: FLUID MECHANICS
Total questions: 126
Worksheet time: 1hrs 3mins
If the energy of the incident photons is less than the work function:
An electron will be ejected
More than one electron will be ejected
An electron will not be ejected
Less than one electron will be ejected
For supersonic, the pressure of fluid must decrease as the fluid flow area of the duct
Increases
Decreases
Remain the same
None of these
Density in terms of viscosity is
Kinematic viscosity / dynamic viscosity
Dynamic viscosity / kinematic viscosity
Kinematic viscosity × dynamic viscosity
None of the above
Liquids and gases take the following characteristics (s) of their contents.
Volume
Shape
Shape and volume
Neither shape nor volume
Alcohol finds in manometers as:
It provides a suitable meniscus for the inclined tube
Its density being less can provide longer length for a pressure difference, thus more accuracy can be obtained
A and B above are correct
Cheap and easily available
Which of the following statement about a Newtonian fluid is most accurate?
Shear stress is proportional to strain
Viscosity is zero
Shear stress is multi-valued
Shear stress is proportional rate of strain
The normal stress is the same in all directions at a point in fluid:
Independent of the motion of one fluid layer relative to an adjacent layer
When there is no motion of one fluid layer relative to an adjacent layer
Only if the fluid is frictionless
Only if fluid is frictionless and incompressible
Which of the following is not a characteristic of pressure?
It is the same in all direction at a point in the fluid
It acts normal to a surface
It is a shear stress
It is linear with depth
The length of mercury column at a place at an altitude will change with respect to that at ground in,
A linear relation
A parabolic relation
Will remain constant
First slowly and then steeply
All of the following dimensionless parameters are applicable to the flow fluid problems except the ________.
Reynolds number
Froude number
Mach number
Blot number
Mass density of liquid (p) is given by which of the following?
p = mass / volume
p = metric slug / m2
p = kg sec2 / m4
All of the above
The speed of sound in all fluids is most closely related to all f the following properties except ________.
Compressibility
Density
Bulk modulus
Thermal conductivity
Under which condition, the specific weight of water is 1000 kg/m3?
At normal pressure of 760 mm
At 4°C temperature
At mean sea level
All of the above
All of the following can be characteristics of fluids except ________.
Kinetic viscosity
Surface tension
Bulk modulus
Hysteresis
Which of the following can be used to measure the flow of water in a pipe of diameter 3000mm?
Venturimeter
Rotameter
Nozzle
Pitot tube
The pressure at a given depth due to several immiscible liquids is:
The average of the individual pressures
The sum of the individual pressure
Independent of the individual pressures
Unknown
The equation of continuity of flow is applicable if:
The flow is one dimensional
The flow is steady
The velocity is uniform over the cross-section
All of the above conditions are together
Uniform flow takes place when:
Condition remain unchanged with time at any point
Rate of change of velocity of fluid is zero
At every point the velocity vector is identical in magnitude and direction for any given instant
The change in transverse direction is zero
The continuity equation of an ideal fluid flow:
States that the net rate of in-flow into any small volume must be zero
Applies to irrotational flow only
States that the energy remains constant along streamline
State that energy is constant everywhere in the fluid
A pitot tube can be used to measure fluid velocity as described by the Bernoulli’s equation and the relationship between:
Kinetic energy and static pressure
Fluid pressure and height of the fluid
Fluid pressure and impact energy
Pressure and momentum
In order to avoid vaporization in the pipe line, the pipe line over the ridge is laid in such a way that it is not more than:
2.4 m above the hydraulic gradient
6.4 m above the hydraulic gradient
10.0 m above the hydraulic gradient
5.0 m above the hydraulic gradient
The stream function is a useful parameter in describing __________.
The conservation of mass
The conservation of momentum
The conservation of energy
The equation of state
For high speed flow, the potential energy of the fluids are:
Positive
Negative
Negligible
None of these
McLeod gauge for low pressure measurement operates on the principle of __________.
Gas law
Boyle’s law
Charles law
Pascal’s law
A Kaplan turbine is
A high head flow turbine
An impulse turbine, inward flow
A reaction turbine, outward flow
Low head axial flow turbine
The most common method for calculating frictional energy loss for laminar flowing fluids in noncircular pipes is:
The Darcy equation
The Hagan–Poisevill equation
The Hazen–Williams equation
The Swamee–Jins equation
The parameter f in the expression for head-loss is
The fraction of flow that is totally turbulent
The darcy friction factor
The height of the roughness scale in turbulent flow
The static coefficient of friction
Friction factor for both laminar and turbulent flows can be found plotted in a
Steam table
Psychrometric chart
Moody diagram
Mollier diagram
Which of the following is relative velocity?
The difference between two velocities
Average velocity
Sum of two velocities
Vector difference of two velocities
Which of the following is the highest head?
33 inch Hg
31.0 ft. water
1.013 kg/cm2
75.0 cm of Hg
For stable equilibrium of floating body its metacenter
Below the center of gravity
Below the center of buoyancy
Above the center of buoyancy
Above the center of gravity
Center of pressure of an inclined plane lies ________
At he centroid
Above the centroid
Below the centroid
At metacenter
The line of action of the buoyant forces always acts through the centroid of the ________
Submerged body
Volume of the floating body
Volume of the fluid vertically above the body
Displaced volume of the fluid
The hydraulic grade line of a pipeline denotes which of the following?
Total energy
Pressure energy
Potential energy
The sum of pressure energy and potential energy
The energy grades line of a pipeline denotes which of the following
Total energy
Pressure energy
Potential energy
The sum of pressure energy and potential energy
The presence of friction in the energy grade line will always cause the line to slope
Down in the direction of the flow
Upward in the direction of the flow
Level (no slope)
There is no effect of friction on the energy grade line
The pitot tube is a device used for measurement of
Pressure
Flow
Velocity
Discharge
Hydrometer is used to find out
Specific gravity of liquids
Specific gravity of solids
Specific gravity of gases
Relative humidity
The fluid forces taken into consideration in the Navier-Stokes equation are:
Gravity, Pressure and viscous
Gravity, pressure turbulent
Pressure, viscous and turbulence
Gravity, viscous and turbulence
Permissible velocity of water flowing through concrete tunnel, is generally
4 – 5 m/s
10 – 12 m/s
13 – 16 m/s
20 m/s
Orifice refers to an opening
With closed perimeter and regulating from through which water flows
With prolonged sides having length of 2 to 3 diameters of opening in the thick wall
With partially full flow
In hydraulic structure with regulation provision
The value of coefficient of discharge in comparison to coefficient of velocity is found to be ________.
More
Less
Same
More/less depending on flow
Weir refers to an opening
Having closed perimeter and of regular form through which water flows
Having prolonged sides with length of 2 to 3 diameters of opening in thick wall
Having partially full flow
In hydraulic structure with regulation provision
Which of the following parameters determine the friction factor of turbulent flow in a rough pipe?
Froude number and relative roughness
Froude number and Mach number
Reynolds number and relative roughness
Mach number and relative roughness
Power transmitted through a pipe is maximum when the loss of head due to friction is:
One-half of the total head supplied
One-third of the total head supplied
One-fourth of the total head supplied
Equal to the total head supplied
In a nozzle if back pressure is same as inlet pressure; then __________.
No flow takes place
Maximum flow takes place
Flow becomes subsonic in diverging section
Flow becomes supersonic in converging as well as supersonic section
The flow on two sides of a normal shock wave is called _________.
Sonic
Sub-sonic
Supersonic
Supersonic on one side and sub-sonic on the other side
Which of the following is the basic of Bernoulli’s law for fluid flow?
Continuity equation
Principle of conservation of energy
Fourier’ law
Principle of conservation of mass
Which of the following is NOT a characteristic of fluid pressure?
It is shear stress
It is the same in all direction at a point in the fluid
It acts normal to a surface
It is linear with depth
Refers to the compressibility of a fluid, the fractional change in fluid volume per unit change in fluid,
Viscosity
Bulk modulus
Density
Pressure
A pitot tube can be used to measure fluid velocity as described by the Bernoulli equation and the relationship between:
Kinetic energy and static pressure
Fluid pressure and static pressure
Fluid pressure and impact energy
Pressure and momentum
The ratio of the area to the wetted perimeter is known as ________.
Flow factor
Hydraulic radius
Kutter’s C
Value of k in darcy – weisbach formula
What is the coefficient of contraction?
The ratio of the area of vena contracta to the area of the orifice
The ratio of actual discharge to the theoretical discharge
The ratio of the actual velocity to the theoretical velocity
The ratio of the effective head to the actual head
Where is vena contracta most likely located?
At the orifice
At a distance approximately ½ the diameter of the orifice
At a distance approximately equal to the diameter of the orifice
At a distance approximately twice the diameter of the orifice
A substance that is able to flow and yields to any force tending to change its shape without changing its volume such as water and air.
Fluid
Flux
Gas oil
Water gas
The velocity of a fluid particle at the center of the pipe section is _________.
Maximum
Minimum
Average
Logarithmic average
For supersonic flow, the pressure of the fluid must increase as the fluid flow area of the duct;
Increases
Decreases
Constant
None of these
Which is incorrect statement regarding apparent shear forces.
It can never be found in frictionless fluid regardless of its motion
It can never be found when the fluid is at rest
It depends upon cohesive forces
It may occur owing to cohesive when the fluid is at rest
The time required for half a quantity of radioactive particles to decay (disintegrate) is called its ________.
Average life
Median life
Time Constant
Half time
SI unit of viscosity is;
10 times poise
9.81 times poise
1 / 9.81 times poise
1 / 10 time poise
For computation convenience, fluid are usually classed as:
Rotational or irrotational
Real or ideal
Laminar or turbulent
Newtonian or non-Newtonian
Which of the following is not a dimensionless parameter?
Kinetic viscosity
Weber number
Darcy Weisbach friction factor
Froude number
Which of the following is not a characteristic of real fluids?
Finite viscosity
Non–uniform velocity distributions
Compressibility
Experience of eddy currents and turbulence
Which of the following is not the mass density of water?
62.5 lbm/ft3
100 kg/m3
1 g/cm3
1 kg/L
The upper critical Reynolds number for pipe flow is:
Of no practical importance to designers
Always used to design pipes for strength
The number at which turbulent flow changes over to laminar flow
The number at which laminar flow changes into turbulent flow
Which of the following statements about gauge pressure is most correct? Gauge pressure are measured relative to ________.
Atmospheric pressure
A vacuum
Each other
The surface
The volumetric change of the fluid caused by a resistance is called ________.
Volumetric strain
Volumetric index
Compressibility
Adhesion
Compressibility of a fluid relates the fractional change in fluid volume per unit change in fluid.
Temperature
Density
Pressure
Viscosity
Property of a fluid whereby its own molecules are attracted is known as ________.
Adhesion
Cohesion
Surface tension
Viscosity
The term subsonic flow refers to a flowing gas with a speed:
Less than the local speed of sound
Equal to the speed of sound
Greater than the speed of sound
Much greater than the speed of sound
The pressure at a point in a fluid will not be same in at the directions if the fluid is:
Viscous
Viscous and static
Inviscous and in motion
Viscous and is in motion
The statement that the hydrostatic pressure at a fluid exerts on an immersed object or on container walls is a function only of fluid depth is
The perfect gas law
D’Alembert’s paradox
The hydrostatic paradox
Boyle’s law
Bernoulli’s equation is s/an __________.
Momentum equation
Conservation of energy equation
Conservation of mass equation
Equation of state
An ideal fluid is one that:
Is very viscous
Obeys Newton’s law viscosity
Is assumed in problems in condult flow
Is frictionless and incompressible
The relation between pressure and attitude in the atmospheric is given by the:
Perfect gas law
Conservation of mass
Barometric height relationship
First law of thermodynamics
The fact the buoyant force on a floating object equal to the weight of the water displaced is:
Bernoulli’s law
Archimedes principle
The law of diminishing returns
The conservation of mass
Which of the following terms does not appear in the steady flow energy equation (the extended Bernoulli’s equation)?
Kinetic energy
Potential energy
Friction losses
Hysteresis losses
Neglecting the force due to inertia, gravity and frictional resistance, the design of a channel can be made by comparing
Weber number
Reynolds number
Froude’s number
Prant’l number
The difference between stagnation pressure and total pressure is:
Due to height difference
Due to kinetic energy
None of the terms are interchangeable
Important only in supersonic flow
Fully turbulent flow in a pipe is characterized by all of the following except;
A parabolic velocity profile
A momentum exchange due to fluid masses rather than molecules
A maximum velocity at the fluid center line
A 1/7 velocity profile
The laminar friction factor of fluid flowing through pipe is a function of all of the following except:
Fluid velocity
Pipe diameter
Pipe roughness
Reynolds number
The continuity equation is a applicable to:
Viscous unviscous fluids
Compressibility of fluids
Conservation of mass
Steady unsteady flow
The rise or fail of head 'h' in a capillary tube of diameter 'd' and liquid surface tension 's' and specific weight 'w' is given by:
4s/wd
4ds/w
4wd/s
4ws/d
The study of the practical laws of fluid flow and the resistance of open pipes and channels
Fluid mechanics
Hydraulics
Aerodynamics
Thermodynamics
Which of the following turbine is different from the others?
Fourneyrón turbine
Francis turbine
Kaplan turbine
Prelton wheel
Running away seed of a Pelton wheel gives;
Actual operating speed
No load speed
Full load speed
No load speed when governor mechanism fails
Which of the following turbine is different from the others?
Pelton wheel
Banki turbine
Jonval turbine
Kapitan turbine
The characteristic length of the Reynold's number to calculate the friction in noncircular full running pipe is based on the ______.
Run length
Pipe length
Hydraulic diameter (the equivalent diameter)
Wetted circumference
The hydraulic radius of noncircular pipe is:
The square root of the flow area
The ratio of the area to the wetted perimeter
The radius of the pipe of equivalent area
None of the above
The Darcy equation can be used for all liquids and flow except:
Water
Alcohol
Gasoline
Air flowing supersonically
The Hazen – Williams formula for head loss due to friction is based upon:
Rigorous mathematical derivation
Empirical data
Semi – empirical analysis
Srendipity
The extended Bernoulli equation includes all of the following terms except:
Potential energy
Kinetic energy
Nuclear energy
Friction losses
An equipotential line is one that;
Has no velocity component tangent to it
Has uniformly varying dynamic pressure
Has no velocity component normal to it
Exist in case of rotational flow
What is the use of a hydraulic jump?
Increase te flow rate
Reduce the flow rate
Reduce the velocity of flow
Reduce the energy of flow
What do you call the lowest portion to storage basin from where the water is not drawn?
Bottom storage
Sub soil storage
Spring reserve
Dead storage
The presence of friction in the hydraulic grade line will always cause the line to slope:
Down in the direction of the flow
Upward in the direction do the flow
Level (no slope)
There is no effect of friction on the energy grade line
The presence of a minor loss in the energy grade line will cause the line to slope:
Down in the direction of the flow
Upward in the direction of the flow
Vertically downward
There is no effect on the energy grade line
What do you call the pressure which the fluid exerts on an immersed objects or container walls?
Normal pressure
Standard liquid pressure
Hydrostatic pressure
Gage pressure
Viscosity for a fluid is defined as the constant of proportional between shear and what other variable?
The spatial derivative of velocity
The time derivative of pressure
The time derivative of density
The spatial derivative of density
What is the classification of the fluid flow if the fluid travels parallel to the adjacent do not layers and the paths of the individual particles do not cross each other?
Steady flow
Laminar Flow
Uniform flow
Turbulent flow
Which of the following refers to the measure of a fluid's sensitivity to changes in viscosity with changes in temperature?
Viscosity index
Coefficient of viscosity
Viscosity ratio
Viscosity factor
IF the number is greater than 1 but lesser than 5, what is the standard classification of the travel?
Transonic travel
Subsonic travel
Hypesonic travel
Supersonic travel
What is measured by a Pitot tube?
Volumetric discharge
Mass flow
Pressure
Velocity
What is the difference between the energy grade line and the hydraulic grade line?
Potential energy
Pressure energy
Kinetic energy
Friction losses
Kinetic energy is not neglected in calculations of:
High speed flow
Low speed flow
Steady flow
Equilibrium flow
Discharge losses through an orifice are due to:
Friction losses
Minor losses
Both friction and minor losses
Pressure losses
Which of the following is considered as an important parameter in the study of compressible flow?
Speed of fluid
Speed of sound
Speed of light
Speed of fluid flow
The velocity at which an infinitesimal small pressure wave travels through a medium is:
Subsonic velocity
Hypersonic velocity
Sonic velocity
Monatomic velocity
It is the ratio of the actual velocity of the fluid to the velocity of sound.
Mach number
Froude number
Sonic number
Euler number
The flow is called sonic when Mach number is:
Equal to 1
Less than 1
More than 1
None of these
The following flow is subsonic when Mach number is:
Greater than 1
Less than 1
More than 1
None of these
The flow is supersonic when Mach number is:
Greater than zero
Less than 1
Greater than 1
None of these
The flow is transonic when:
M = 0
M < 1
M > 1
M = 1
The pressure decrease as the temperature and velocity increase while the fluid velocity and Mach number:
Increases
Decreases
Remains constant
None of these
The Mach number is unity or one at the location of smallest flow area, called the:
Decreasing area
Throat
Increasing area
None of these
Which of the following is an example of a Newtonian fluid?
Motor oils
Gas
Paints
Clay slurries
What is the pressure of water?
150 kg/cm3
Less than 200 kg/cm2
More than 200 kg/cm2
100 kg/cm2
The volumetric change of the fluid caused by a resistance is called:
Volumetric change
Volumetric index
Compressibility
Adhesion
The energy of a fluid flowing at any section in a pipeline is a function of:
Velocity of flow only
Pressure only
Height above a chosen datum, density, internal energy, pressure and velocity of flow
Pressure, height above a chosen datum, velocity of flow, density of liquid
If the fluid travels parallel to the adjacent layers and the paths of individual particles do not cross, the fluid is said to be:
Turbulent
Critical
Dynamic
Laminar
Center of pressure on an inclined plane lies:
At the centroid
Above the centroid
Below the centroid
At the metacenter
At any instant, if the number of particles passing every cross-section of the stream is the same, the flow is said to be:
Steady flow
Uniform flow
Continuous flow
Laminar flow
The ratio of cross-sectional area of flow to the wetted perimeter is:
Hydraulic head
Hydraulic section
Hydraulic mean depth
Hydraulic gradient
If A is the cross-sectional area of the flow and Pw is the wetted perimeter of a pipe, then what is the hydraulic depth, Hd?
Pw − A
Pw / A
A / Pw
Pw × A
If Q is the volume in gallon; D is height or elevation in ft, and m is weight in lbs per gallon, what is the desired energy to lift the water from lower to higher elevation?
E = mD/Q
E = mDQ
E = mQ/D
E = QD/m
The flow of the convergent section of a nozzle is always subsonic. If the flow is subsonic then the Mach number is:
Greater than unity
Less than unity
Near unity
Unity
